Seating Depth

Powderfinger61

Powderfinger61

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I have a Savage FTR .308
I deceided to move my bullet as close to the grooves as possible.
You can see the marks on the bullet and the OAL is under 2.8.

Am I doing something wrong or does this sound correct.
Lapua Brass
Sierra 155 gr SMK

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Thanks for any help
 
mooger31 said:
I will admit I'm not a expert in reloading yet. But what do you mean by the grooves? Do you mean where the lands of the rifling starts?
Click to expand...

grove and lands both make up the rifling, lands being the high parts groves the low parts


OP it could be that you have a very short throat in your rifle, example, in my 700 im at like 2.875 IIRC with 175SMK and thats still .015 off the rifleing. how are you determining your MAX OAL befor your jamed into the lands?
 
The best way to be sure, it to load an empty brass, no primer, no powder, with a bullet. Then pull the bullet (this will loosen up the neck tension), then re-seat at a length of about 2.95 or 3.0 if you can keep it in the case.

Then chamber the cartridge, it should shorten to the OAL where it touches the lands, do this at least 3 times and take the average OAL.

This is called Jam seating to determine OAL at teh lands
 
That is about right for a 2155 bullet. Robeti11 is correct too. There are many variations on the same theme like cutting slices into the neck with a dremel tool to lightly grab the bullet. of course you need to take multiple measurements because sometimes the rifling will grab the bullet and hang onto it. do yourself a favour and get a comparator. measuring off the bullet tip is a crude measurement. If you start using VLD bullets, the error can be enough to cause problems.

one way to help offest this error is to use the very same bullet that you used for your measuring in a tight case set to the length you measure and use it to set up your die. the seating stem will act like a bit of a comparator, at least it won't touch the tip of the bullet from round to round.
 
I went with a few rounds tonight to see how this seating depth worked out. I deceided to use 45gr Varget as a starting point as I was using Fed Mag primers and wanted to watch for pressure signs.
utf-8BSU1HLTIwMTIwODIzLTAwNjY5LmpwZw.jpg

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The sweet spot with most 155s seems to be around 46.5-47gr of Varget if you can get there safely. I couldn't believe how well the 2155s shot out of my 10 twist at 46.5gr, and jumped 40 thou.
 
ya your shorter oal is fine ,ive done this with my rifle, seated off the lands 10-20thou tested and seen what worked best, just watch for overpressure signs.
 
Along the same line....

Has anyone done this with 175gr SMKs? I'm measuring ~2.950 against the lands.

This seems awfully long to me... :S
 
It is what it is Franklin. As long as it shoots who cares. The only downside might be if your running a mag. You may have to seat to mag length and forget everything else. I run my 175 Mks with 44.8 gr of varget, seated to mag length and they still shoot into an inch at 200m. Match kings are very tolerant bullets.
 
Yes, mag use is definitely out of the question! I asked only because I am only beginning to develop some loads for the gun, so I have no idea how anything shoots out of it currently.
 
Rifles come with a huge variety of throat lengths. Remingtons are deep. looks like the Savage is shallow. Don't argue withthe rifle.

I have see 2.800 touch the rifling ina new rifle, so the OP is not unusual.

Why the Mag primer?

Run a test of touching and then 10 thou increments shorter. Find out if your rifle/bullet likes to touch or to jump. most prefer a jump. Once you know that, you can try more powder.
 
TO add to the jam length of what Roberti11 said set it long close the bolt without the firing pin assembly, check the length. next step pull the bullet, resize the neck with the same neck tension and lube the base of the bullet and inside the neck. Do the excerise again the lube will reduce the friction and give you a truer jam to land length. I have started using this technique with good results. (thanks tony boyer)

Trevor
 
Trevor60 said:
TO add to the jam length of what Roberti11 said set it long close the bolt without the firing pin assembly, check the length. next step pull the bullet, resize the neck with the same neck tension and lube the base of the bullet and inside the neck. Do the excerise again the lube will reduce the friction and give you a truer jam to land length. I have started using this technique with good results. (thanks tony boyer)

Trevor
Click to expand...

To add to the add to list, I do similar, except I use once fired brass for that chamber un sized & I lube the neck with 5 min epoxy muzzle down and bullet of choice (Matrix) close the bolt. and presto, without engraving I have a perfect length to the lands. no fuss no muss.

But as mentioned, if it shoots who cares.



M
 
FTRRookie said:
The sweet spot with most 155s seems to be around 46.5-47gr of Varget if you can get there safely. I couldn't believe how well the 2155s shot out of my 10 twist at 46.5gr, and jumped 40 thou.
Click to expand...

I'm at the same weight range but it's tough to comment on OAL as each bullet could be different so measuring the ogive will be easier. However, I am setting my loads for .308 Savage at about 2.95 or so
 
Mag Primer

[
Why the Mag primer?

I learned from an accomplished long range shooter from the Island (Vancouver). He steered me towards Mag primers for the bit more bang they may give. Same size ( I assumed) but a bit more of a charge to ensure the ignition gets to the powder. I have been loading my 308 with mag primers ever since (except when using BR primers).

Truth or Fiction??????
 
Group Size

Powderfinger - Your selling yourself short on your group size I think?? Go center to center. It looks like your measuring from about half to 2/3's the way between the center and the outer edge of the bullet hole. Either way - thats good shooting.
 
OP,
You might even be seating them too long for that Savage chamber. I'm learning with Savage sometimes you have to get out of the lands and sometimes you gotta be right in them.

I just discovered this morning that I had to seat those 155 grain SMKs your trying out, much deeper than I had been in one particular savage.

EDIT: 155 SMKs using Hornady 30 cal comparator insert OAL = 2.114" I don't have one made up to measure but the overall length base to bullet tip was below 7.35".
Much shorter than I would have expected. A little longer and sub MOA groups at 300 yards would turn into 4 and 5 inches. This is a BVSS barrel FWIW.
 
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